The field of the present invention relates to synchronously pumped optical parametric oscillators. In particular, apparatus and methods are disclosed herein for alignment and optimization of a synchronously pumped optical parametric oscillator for nonlinear optical generation.
A wide variety of optical parametric oscillators (OPO's) have been described previously, as well as schemes for nonlinear optical generation that employ OPO's. Some of these are described in:    U.S. Pat. No. 5,017,806 entitled “Broadly tunable high repetition rate femtosecond optical parametric oscillator” issued May 21, 1991 to Edelstein et al;    U.S. Pat. No. 5,212,698 entitled “Dispersion compensation for ultrashort pulse generation in tunable lasers” issued May 18, 1993 to Kafka et al;    U.S. Pat. No. 5,365,366 entitled “Synchronously pumped sub-picosecond optical parametric oscillator” issued Nov. 15, 1994 to Kafka et al;    U.S. Pat. No. 5,371,752 entitled “Optical parametric oscillation using KTA nonlinear crystals” issued Dec. 6, 1994 to Powers et al;    U.S. Pat. No. 5,377,043 entitled “Ti:sapphire-pumped high repetition rate femtosecond optical parametric oscillator” issued Dec. 27, 1994 to Pelouch et al;    U.S. Pat. No. 5,406,408 entitled “Intracavity-doubled tunable optical parametric oscillator” issued Apr. 11, 1995 to Ellingson et al;    U.S. Pat. No. 5,847,861 entitled “Synchronously pumped sub-picosecond optical parametric oscillator” issued Dec. 8, 1998 to Kafka et al;    U.S. Pat. No. 6,282,014 entitled “Cascade optical parametric oscillator for down-conversion” issued Aug. 28, 2001 to Long et al;    U.S. Pat. No. 7,272,158 entitled “Highly efficient waveguide pulsed THz electromagnetic radiation source and group-matched waveguide THz electromagnetic radiation source” issued Sep. 18, 2007 to Hayes et al;    U.S. Pat. No. 7,339,718 entitled “Generation of terahertz radiation in orientation-patterned semiconductors” issued Mar. 4, 2008 to Vodopyanov et al;    U.S. Pat. No. 7,349,609 entitled “Terahertz radiation generation and methods therefor” issued Mar. 25, 2008 to Vodopyanov et al;    U.S. Pat. No. 7,616,304 entitled “System and method for providing a tunable optical parametric oscillator laser system that provides dual frequency output for non-linear vibrational spectroscopy and microscopy” issued Nov. 10, 2009 to Gankkhanov et al;    U.S. Pub. No. US 2008/0037595 entitled “System and method for providing a tunable optical parametric oscillator laser system that provides dual frequency output for non-linear vibrational spectroscopy and microscopy” published Feb. 14, 2008 in the names of Gankkhanov et al;    Pub. No. WO 2007/132229 entitled “Optical parametric oscillator” published Nov. 22, 2007 in the names of Ebrahim-Zadeh et al;    Pub. No. WO 2008/135257 entitled “Method and optical arrangement for generating a nonlinear optical signal on a material which is excited by an excitation field, and use of the method and of the optical arrangement” published Nov. 13, 2008 in the names of Rimke et al;    Kieu et al; “High-power picoseconds fiber source for coherent Raman spectroscopy”; Optics Letters vol 34 p 2051 (2009);    Saar et al; “Intracavity wavelength modulation of an optical parametric oscillator for coherent Raman microscopy”; Optics Express vol 17 p 12532 (2009);    Schaar et al; “Intracavity terahertz-wave generation in a synchronously pumped optical parametric oscillator using quasi-phase-matched GaAs”; Optics Letters vol 32 p 1284 (2007);    Lee et al; “Generation of multicycle terahertz pulses via optical rectification in periodically inverted GaAs structures”; Applied Physics Letters vol 89 p 181104 (2006);    Vodopyanov et al; “Resonantly-enhanced THz-wave generation via multispectral mixing inside a ring-cavity optical parametric oscillator”; Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (Optical Society of America, 2009), CLEO paper CTuG1;    Kokabee et al; “Efficient, high-power, 16-GHz, picosecond optical parametric oscillator pumped by an 81-MHz fiber laser”; Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (Optical Society of America, 2010), CLEO paper CThP2; and    Hurlbut et al; “THz-wave generation inside a high-finesse ring-cavity OPO pumped by a fiber laser”; Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, OSA Technical Digest (Optical Society of America, 2010), CLEO paper CWF3.